CINCINNATI—Folic acid—a B vitamin used by the body to produce new cells—is most often recommended to pregnant women for the prevention of major birth defects.

This compound (called folate in its naturally occurring form) is found most abundantly in green leafy vegetables, fruits and beans and has been studied for the prevention of cancer, stroke and heart disease.

Recently, says University of Cincinnati (UC) psychiatrist Erik Nelson, MD, research has shown that people with depression are more likely to have low levels of folic acid.

And findings reported 10 years ago in the American Journal of Psychiatry suggest that people deficient in folate respond less well to depression medication than those with normal folate levels.

This, Nelson says, leads many to believe that adding folic acid to a regular depression treatment may be beneficial.

People with depression often have low levels of serotonin—a neurotransmitter believed to be involved in modulating anger, aggression, mood and appetite, among other things.

A certain class of medications, called selective serotonin re-uptake inhibitors (SSRIs), is used to regulate the amount of serotonin in the brain. And folate is believed to be involved in the synthesis of serotonin—making it a natural modulator of this chemical.

Nelson, an associate professor of psychiatry, is currently studying whether a particular folic-acid derivative—when added to a common SSRI—can improve outcomes for people suffering from depression.

“We know that many people with depression have low folate levels,” says Nelson. “We aren’t sure if that deficiency leads to depression or if the depression is causing the deficiency.

“But knowing that people with low folate levels have a poorer response to medication leads us to believe we may be able to add this supplement to depression treatment and improve outcomes.”

Folic acid can be incorporated into diets through food selection or by supplements. Nelson cautions, however, that the benefits of adding folic acid to a depression treatment plan are not yet fully understood and that folic acid by itself, or in combination with antidepressants, is currently not a proven treatment for depression. He recommends consulting a physician before adding any supplement to your diet.